stax mafia circuit boards see updated links on page 5

[Helium]

On 10.05.2017 at 8:25 PM, spritzer said:

Given Kevin's retirement, we had to move the files so I put them here temporarily.  I might move them again soon though....

Could you upload there schematic files as well please?

[xianghao]

On 2017/5/11 at 3:43 AM, kevin gilmore said:

the whole archive is 20GB and is a real mess, lots of cleanup needed, so many different version etc.

here is the one you asked for.

goldenreference.PDF

if anyone needs other pdf's and know the name, I can add here

Kevin, could you add the GG schematic here?  thx

[kevin gilmore]

no idea what the name is

 

[Helium]

Grounded Grid?

[mypasswordis]

He means the name of the file...

[kevin gilmore]

try this, there should be over 300 files, had to remove a couple of confidential ones

 

see updated links on page 5

 

Edited May 25, 2023 by kevin gilmore

[Helium]

wow thank you!

[Pars]

Are the SS DynaFet gerbers available? Couldn't find at the link in spritzer's 5/10 post, nor Kevin's 9/4 post.

Were the balanced Dynahi and FET boards done in 2011 for Lil'Kinghts GB the SS versions? They look like it, but I could be wrong... I attached the schematic I have.

What FETs were these targeted for? The BOM he had showed 2SJ76/2SK213s, but for some reason (availability), I thought the last version used something else?

 

 

 

dynafetschembal.pdf

[kevin gilmore]

I doubt that I ever did a ss dynafet.  I will look.

the latest dynahi and dynalo are both super symmetry, not sure which versions are the lil-knight versions

current versions would use either the that340 parts, or a matched quad of linear systems fets

[Pars]

Thanks Kevin,

The SuSy architecture must be fairly subtle in terms of it versus your normal differential balanced.

Here is what I had for a schematic for the dynafet balanced vs. the SS dynalo (input sections only):

I'll quit crapping on the stax mafia thread also.

[JoaMat]

When I try to open gerbers, probably of newer version,  in Proteus I get warning about “Bottom SMT Paste Mask” and file won’t open. After deleting corresponding line in the readme file it opens nicely in Proteus. What might the reason be that it won’t open without delating that particular line in readme file.

[kevin gilmore]

All the newer gerber x2 stuff most likely. Can't make older gerber files with the new software

[JoaMat]

I use Proteus v8.5, isn't that the software you are using? I guess you are able to open gerbers you made yourself. Can it be some software setup I've missed?

[kevin gilmore]

8.7 sp1 as of 1 month ago,  but a lot of the stuff should be 8.4 or earlier

try a standard gerber viewer. there should be no configuration or setup issues

 

[JoaMat]

All right, I rather prefer to open you gerbers  in Proteus and save them as pdspnl files – works great. Thanks a lot for all work you have done!

[eggil]

.

Edited March 9, 2018 by eggil

[lkong]

Anywhere I can find Uberamp 2 board files?

Or better spare boards.

[sorenb]

I might have two sets I want to depart with 2mm/4oz

[UFN]

Looks like someones been digging in Kevin's archive again ?

Carbon

Megatron

[penmarker]

People are gonna kill themselves building it

[Xenon]

Looking for opinion from those familiar with the KGSSHV amp.

I am thinking of building an electrostatic amp and acquire suitable headphones.  Never having had electrostatic equipment before I expect a step up in quality from my open ear Beyers with dedicated amp.  I do have the practical experience and technical know how to build and test these amplifiers. 

Assuming that even the most basic electrostatic amp and headphones will outperform my existing dynamic setup, I would not need the very best of the best, just something decent.

Q1  Considering my existing equipment and expectation, would you recommend an alternative amplifier to build over the KGSSHV?

Q2  Should I instead just go and buy a basic STAX system?

Q3  All electrostatics use a high voltage, so why would the Carbon and Megatron be perceived as being especially hazardous to build?

 

 

 

[gepardcv]

A1. The KGSSHV uses some out-of-production transistors. While you can still buy them, fakes can be a problem, and reputable suppliers (like bdent) charge a premium. The Carbon is essentially a strict upgrade from the KGSSHV, with (I believe) all current production parts. The major advantage of the KGSSHV over the Carbon is the availability of versions with on-board heatsinks, which simplifies the metalworking considerably. You might consider building a KGST instead. It’s a great amp, and aside from matching 6S4A tubes, I found it generally pretty easy to make. Also consider the SRX Plus (though I haven’t made one of those yet). Search here for threads discussing these builds.

A2. Only you can decide that. It pays to try before you buy.

A3. The Carbon and Megatron are no more dangerous to build than any other device operating at comparable voltages.

[mwl168]

If you prefer to try something that’s simple to build you can also consider Kevin’s current feedback amp. Simple power supply requirement, low parts count and all current parts you can source from Mouser or Digikey.

 

[Hirsch2k]

I am still in the process of sourcing for a KGSSHV Carbon build. Unfortunately I was send one wrong board and I can´t reach the seller any more ?

So, if anyone has a KG SiC PSU PCB in Landscape with +15V -15V -400V I am happy for your PM. Additionally if anyone needs a +400V + Bias PSU, feel free to contact me.

Edit: I got an 8 Dollar coupon at JLPCB so I thougth paying 8,50 dollar for 5 PCBs is probably worth it. 

So I will give away 4 of the +-15V -400V PCBs for cost of shipping. I am located in Germany.

[jamesmking]

On 2/15/2019 at 11:36 PM, Xenon said:

Q2  Should I instead just go and buy a basic STAX system?

You may be happy with a basic stax system but the problem is that if you are not used to electrostatic sound (I also run Quad 2805 electrostatic speakers) there is a big difference in sound to most moving coils. The electrostatics offer very good transparency and speed but for me bass and overall warmth has been an issue that seems to require throwing money at to solve.... 

I have a stax srm006T and sr4040 which I found to be rather bright and the bass was rather mushy. As the volume is turned up the bass gets mushier but no louder and the treble just dominates. It sounds fast and detailed this way but I am very sensitive to poor bass....

I managed to buy a pair of sr007a second hand but could not afford to upgrade the srm006T. to an srm007T. The overall ballance was a bit better than the sr4040s and there was a more natural, less bright and hard sound, but the bass was still mushy and it just ran out of steam even quicker - I guess it could not drive the sr007a...

I built a alpha centauri (http://www.high-amp.de/html/hybrid-amp_eng.html) earlier this year -  The alpha bettered the srm00t in every way It does not run out of steam, macro and micro dynamics are better imaging is better - it was my first serious diy build and I learnt a lot from building it. I was especially grateful that the power supply has full short circuit protection on the +-400V and was extremely robust.... I managed to "measure" the +400V supply with my multimeter in resistance mode ? . Some sparking at the test probes and the 400V went into over current protection... no damage done and months later its still working fine... (the multimeter survived too - a brymen bm869s which can handle 1000V in any imode). The designer of the alpha claims that you can even short the +400 and -400 together and the psu will survive. My only issue with the alpha is that the sound stage is rather flat and has no real depth and mid and upper bass is a bit lacking. .

I read reviews of the blue hawaii and the descriptions made me think it would be my kind of amp - but there was no way I was ever going to afford to buy a prebuilt.... So I’m up for building one...

To summarise, from my experience the modern stax amps from Stax are not good - and they certainly do not have a good reputation online. I think they are over-priced especially given the build quality - thin bent steel. I don’t think the 6cg7 has enough drive to get the job done. The 6sn7 of the alpha is better and I am hopping the el34 of the blue hawaii will be better still... 

If you have the time, equipment and skills to build a diy amp I highly recommend it. You can get far better sound for far less than the commercial offerings and learn a lot in the process.

regards

James